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1/1219The Charles A. Dana Center at The University of Texas at Austin

Science is an active process of learning that builds on students abilities to inquire and

nd out about the natural world. Students become better inquirers when they are

allowed to generate their own questions and design ways to nd answers to those questions

on their own. Scientic investigation allows students to ask questions from which they can apply

methods, build models, and arrive at conclusions that further an understanding of the natural world.Safe practice supports active science learning and independent inquiry.

Laboratory experience is so integral to the nature of science

that it must be included in every science program for every

student. Hands-on science activities can include individual,

small, and large group experiences.

Laboratory Science,

National Science Teachers Association, 1990

LaboratoryInvestigationsand Activities

Science learning experiences occur in the

classroom, in the eld, and in the laboratory.

Through these experiences students discover

facts, concepts, and laws of science, much as

scientists do in their professional lives. Classroom

activities provide students with hands-on

materials and procedures designed to help them

experience various facets of the natural world.

Field experiences allow students to explore,

observe, and investigate aspects of the naturalworld that cannot be brought into the classroom

learning environment.

Learning through Laboratory Experiences

What Is a Laboratory Investigation?

Laboratory settings accommodate different types of instructional strategies and allow teachers and

students to take responsibility for the structure and sequence of an investigative activity.

Laboratory-based investigations allow students

to inquire, explore, and observe natural world

phenomena that are brought into the classroom

specically to facilitate student investigations.

Teachers at all grade levels require a wide

range of materials and instruments to facilitate

student investigations. Safety, therefore, is

an essential part of the planning process,

whether the learning experiences occur in the

classroom, in the eld, or in the laboratory.

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2/1220 Texas Safety Standards 2006

Planning a Safe and Effective Science

Learning Environment,Texas Education Agency, 1985

Verifcation investigation: In this type

of laboratory investigation, the student

determines the cause, effect, nature, or

property of a phenomenon through hands-on

experience under controlled conditions. Theteacher constructs a laboratory procedure,

and the student follows the directionsand,

if successful, conrms known results.

Guided discovery: The teacher presents

students with a problem, and the teacher or

student develops a research design to test

a hypothesis related to the problem. The

teacher guides the process until the student

has successfully tested the hypothesis.

Science inquiry: Students nd answers forthemselves and become involved in learning

how to learn.

Process skill practice: The objective is

to teach manipulative laboratory skills.

However, these skills should be integrated

with science concept activities.

Process skills development: Students have

opportunities to apply scientic processes

to scientic investigations and problem-

solving activities.

Independent study: This arrangement

allows students the opportunity to explore

in greater depth an area of interest not

normally studied by an entire class.

Examples of different types of laboratory investigations include the following.

19, Texas Administrative Code

Chapter 74. Curriculum Requirements

Subchapter A. Required Curriculum

(b) Secondary Grades 912

2(C) science...courses shall include at least 40% hands-

on laboratory investigations and eld work using

appropriate scientic inquiry.

Laboratory investigations and eld work are required by the state curriculum standards, the Texas

Essential Knowledge and Skills, in kindergarten through grade 12. While laboratory and eld work

are required in elementary and middle school science classes, the Texas Education Agency has not

established the percentage of instructional time that is devoted to laboratory and eld investigations at

these grade levels. The National Science Teachers Association recommends that elementary students

spend 80% of instructional time doing hands-on activities and 60% of instructional time for middleschool. This decision is the responsibility of school districts.

School boards should develop a policy that establishes the percentage of time that kindergarten

grade 8 students are to do hands-on laboratory investigations and eld work. The school districts

budget should reect support of this policy by designating appropriate funds for science equipment,

materials, and proper science facilities. School districts may not charge laboratory fees for students in

science classes.

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Demonstrations are an important method of

introducing a science concept or reinforcing

a students understanding of the concept, but

demonstrations by themselves should not beconsidered laboratory investigations.

According to the Texas Education Agency,

demonstrations can be considered part of the

40 percent laboratory requirements.

Computer laboratory simulations are

considered laboratory investigations, but they

should not replace actual hands-on experiences.

As techonology has improved, the level of

experience gained by computer simulations

has also improved. The quality of computer-assisted instruction is now an integral part of

most science classes.

School districts should develop policies on

the types of science activities that will ensure

quality science programs that meet the needs of

their students.

A laboratory investigation consists of pre-

laboratory activities, the laboratory experience,

and post-laboratory activities. Pre-laboratory

activities introduce students to the laboratory

experience. Students can gain important

information about a science concept, plan

strategies for conducting a successful

investigation, and discuss techniques that they

may use during the investigation.

The laboratory experience is the hands-on portion

of the investigation that involves the students

direct participation in activities such as analyzing

information gathered during the laboratory

experience, drawing conclusions, and producing

graphs, maps, charts, or spreadsheets to assistthem with communicating their ndings.

Conclusions may lead to a need for further

investigations, which students and teachers can

discuss and plan during the post-laboratory

activities.

What Qualifes as a Laboratory Investigation?

Laboratory-based experiences begin in the early

grades when students ask questions, plan and

conduct simple descriptive investigations, extend

their senses through the use of tools, construct

reasonable explanations, and communicate their

ndings.

Science experiences in these early grades

allow students to inquire, explore, and observe

phenomena that are brought into the classroom

specically to stimulate student investigations.

Teachers know that students in kindergarten

through grade 2 become better inquirers when

they are allowed to generate their own questions

and design ways to answer those questions on

their own by actively doing science.

Students should follow home and school safety

procedures when participating in classroom

investigations. They should demonstrate safe

practices while learning to use and conserve

resources and materials.

Elementary school students learn science best when they

are involved in rst-hand exploration and investigation and

inquiry/process skills are nurtured.

Elementary School Science,

National Science Teachers Association, 2002

Laboratory Experiences in KindergartenGrade 2

The following summary represents what students are expected to know and be able to do as mandated

in the Texas Essential Knowledge and Skills in Science.

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Laboratory-based experiences in the earlier

grades allowed students to inquire, explore,

and observe things that were brought into the

classroom specically to stimulate student

investigations.

Middle-grade students will become better

inquirers when they are allowed even more

freedom to generate their own questions and

design ways to nd answers to those questions

on their own. Students in grades 68 should

have the freedom to select and use equipment

and technology to implement investigative

procedures.

By grade 8, students should be able to plan

and implement descriptive and experimental

investigative procedures, collect data, organize,

analyze, evaluate, make inferences, and predict

trends in evidence. They should be able to

communicate valid conclusions effectively and

use tools to construct graphs, tables, maps, and

charts.

Students should demonstrate safe practices thatare environmentally appropriate and ethical as

they conduct laboratory investigations and do

eldwork.

Laboratory-based experiences in kindergarten

through grade 2 required the students to plan and

implement descriptive investigations by asking

well-dened questions, formulating hypotheses,

and selecting the equipment and materials needed

to conduct the investigations.

Students in grades 35 can generate their own

questions and design ways to nd answers

to those questions on their own. They can

collect information by observing and taking

measurements, and analyze and interpret that

information to develop reasonable explanations

about the results.

Students should be able to communicate valid

conclusions and, when possible, incorporate

graphs, tables, maps, and charts to organize and

evaluate information.

When conducting eld and laboratory

investigations, students should follow home

and school safety procedures as well as

environmentally appropriate and ethical

practices.

Students should demonstrate safety practices

during the eld and laboratory investigations and

make wise choices in the use and conservation of

resources.

High school teachers should expect students to

be better science learners when they are allowed

the freedom to generate their own questions and

design ways to nd answers to those questionson their own. Students in ninth-grade science

should already have had numerous eld- and

laboratory-based science experiences from

kindergarten through grade 8, and they will

have used a wide range of science materials and

instruments.

By grade 9, students should be able to

demonstrate many of the new science concepts

they are learning. They should be able to plan

and implement descriptive and experimentalinvestigative procedures in which they select

equipment and technology to facilitate their

investigations.

Specialized equipment and procedures facilitate

students conceptual understanding of complex

concepts, many of which require special

precautions to assure student safety in the

laboratory.

Laboratory Experiences in Grades 35



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1. Maintain fair and consistent classroomdiscipline to prevent unsafe conditionsfrom being created during laboratoryinvestigations.

2. Establish routine procedures forconducting a laboratory investigation that

promote an orderly and safe environment.Ask different students in each laboratorygroup to

obtain materials from a supply area,

return materials at the completion of alaboratory investigation, and

record data, if class data are needed.

3. Explain and post the expectationsfor orderly conduct in the classroom,

laboratory, and eld. Teachers shouldalways model appropriate classroom,laboratory, and eld procedures.

4. Explain and post safety rules for theclassroom, laboratory, and eld. Studentsand parents should complete and returna signed safety contract before studentsbegin investigations.

5. Explain the consequences of unsafebehavior.

6. Before each laboratory investigation,review the safety rules for usinglaboratory equipment and facilities.

7. Prior to the investigation, arrange for theproper disposal of wastes.

8. Keep up with current information onsafety and class procedures, and practicethose procedures consistently.

Laboratory Management TechniquesClassroom management techniques maximize and reinforce proper behavior and safety in the science

laboratory. Essential knowledge, concept mastery, and process skill development have high priority

in the science laboratory and depend on effective strategies for maximizing learning. Fortunately,

the techniques that maximize learning also promote safety. The following represents a list of

recommended laboratory management techniques.

9. Examine laboratory investigations andequipment for appropriateness and safety.

10. Review with students the procedures forusing the laboratory. Discuss safety rulesand precautions before the investigationbegins.

11. Promote a positive attitude. Studentsshould not fear doing experiments, usingreagents, or using equipment, but shouldhave a positive attitude toward safelaboratory procedures.

12. Adjust procedures for students withemotional, physical, or educationalproblems to capitalize on the contributionsthey are able to make.

13. When a substitute teacher is in charge,

create an alternate lesson plan that doesnot involve laboratory work.

14. Monitor continuously for maximizedlearning and safe conditions.

15. Plan post-lab activities.

16. Clean the work areas thoroughly andregularly.

17. Develop procedures to be followed in caseof an accident.

18. Establish procedures for asking studentsto leave the laboratory when theydemonstrate unacceptable behavior.

Paraphrased from Secondary Science Safety, by J. G.Gerlovich, T. F. Gerard, B. Shriver, G. E. Downs, and L.C. Flinn, Jr., and from Science Laboratory Techniques,by R. B. Bartholomew and F. E. Crawley, 1985.

Table 5

Laboratory Management Techniques

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Evaluating Saety in Laboratory Investigations

Do not assume that investigations

published in laboratory manuals

or journals, or acquired from other

teachers, are safe.

Always read and check new

investigations carefully.

Appropriate safety symbols should

be present in the investigation to

alert students to a precaution against

a hazard.

The investigation should inquire

into, investigate, illustrate, or

analyze a scientic concept orprinciple in a safe manner or

method.

Check the equipment or setup to be

used and the glassware for proper

assembly and cracks.

Know all the actions and reactions

that should occur between the

chemicals to be used, and investigate

unexpected reactions that mightoccur.

Know the hazards of all substances

used in the activity. Material

Safety Data Sheets (MSDS) and

other safety references should be

consulted.

Know the hazards of predicted

products that may form during the

chemical reactions in the investigation.

The correct amounts of substances and

concentrations of solutions should be

clearly stated in the directions.

Substances with a high hazard rating

should not be used in science labs.

Substitute safer compounds for the

hazardous substance.

Check the electrical equipment for

proper grounding, frayed wires, and

safe connections.

All precautions must be thoroughly

discussed in the pre-lab session with

the students.

The students should be aware of what

to do with the products that are formed

and any remaining materials.

The investigation must be clearly

written so that students understandexactly what to do and how to carry

out the activity.

Laboratory investigations and experiments are handed down from one teacher to another, given away

at conferences, downloaded from the Internet, and found in journals. But how does the teacher know

that the laboratory investigation is safe for students to use?

To evaluate how safe an investigation is, consider these guidelines before allowing students to

conduct an unfamiliar investigation. Remember, the teacher should always complete the investigation

before approving it for student use.

Science Laboratory Safety and Chemical Waste

Disposal for Texas Science Teachers,

Texas Education Agency,1990

Table 6

What Can Be Done in Advance?

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Being prepared for accidents will help decrease the possibility of an accident becoming more severe

or of other injuries occurring. In the event of an accident, action must be taken quickly to minimize

the effects of the accident. It is strongly recommended that teachers receive professional training

in cardiopulmonary resuscitation (CPR), rst aid, abdominal thrust (Heimlich maneuver), and other

emergency procedures.

Planning for an emergency should involve the entire organization within your school: administrators,

maintenance staff, custodial staff, ofce staff, nurse, teachers, students, and parents. Every area and

event should be included in the planning, including the school building and grounds, eld trips, etc.

Possible emergencies that teachers may respond to include . . .

small to moderate res

chemical reactions that result in an explosion serious burns resulting from exothermic reactions

serious chemical burns

ingestion of hazardous chemicals

electrical shocks from equipment

chemical spills resulting from broken containers

minor to serious cuts

1. Attend to the injured person(s) immediately.

2. Administer rst aid in the laboratory to . . .

stop the ow of blood in the case of a

cut, and

wash off any caustic chemicals on the

body or in the eyes.

Special Note: Teachers should wear protective

gloves before handling victims who are bleeding.

3. If the injury is a cut or an abrasion . . .

wash the injured area thoroughly.

place a compress on the wound to

stop the ow of blood.

replace the compress with a sterile

bandage if the injury is minor.

accompany the student to the nurses

ofce if the injury is moderate or severe.

follow the proper procedures to clean up

blood.

4. If the injury is the result of chemicals . . .

rush the injured person to the safety

shower (safety showers should be

within 10 seconds of any student

approximately 50 feet away).

immediately drench the entire area

with a continuous ow of water for 15

minutes.

send a student to alert the schools

nurse or to get another teacher.

use a spill kit to contain and remove

the chemicals.

5. If foreign materials or chemicals have

entered the eye . . .

rush the student to the dual eyewash

station (eye/face washes should be

within 10 seconds of any student).

Common Emergencies

I an Accident Occurs

Responding to a Laboratory Accident

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remember, the student will have

difculty seeing, so guide him or her to

the eye/face wash station.

rinse the open eyes with a continuous

stream of tepid water (6090oF) for 15

minutes.

send a student to alert the schools

nurse or another teacher.

6. If the injury is the result of electrical shock . . .

separate the person from the electrical

source carefully. Use the master control

switch.

call for emergency medical aid

immediately.

check for breathing and pulseimmediately.

start CPR if necessary.

check for entrance and exit burns. Treat

burns as you would a thermal burn.

there may be two burns presentone

where the power entered the body and

the other where it exited. Some burns

are large and below the skin.

keep the injured person warm, quiet, and

lying down.

the injured person may stop breathing

after being shocked by high-frequencyelectrical currents or being struck by

lightning.

the injured person may be unconscious,

dazed, weak, or confused, with an

irregular pulse.

7. The nurse should assume responsibility for

providing help at this point by . . .

administering additional rst aid,

contacting the parents, and

pursuing additional treatment if

necessary (information is on students

emergency health cards).

8. If the nurse is not available, the teacher is

obligated to follow through with accident

procedures to protect the student from

further injury.

The teacher or nurse should call the

students parents to advise them of the

severity of the accident and to ask their

permission to proceed with treatment asneeded.

If the parents cannot be reached, the

teacher must act in accordance with the

situation. The students emergency

health card gives permission for

emergency care to be administered. The

teacher should call a physician and,

upon the physicians advice, seek

treatment for the injured student.

9. After the injured person has been cared

for and any chemical spill contained, theteacher needs to ll out an accident report

for their own protection even if it is not

required by the school district.

Regardless of how good the science facilities are, how well we are

trained on safety, how much emphasis we place on safe procedures

accidents are going to happen. How well we respond to accidents

depends on how well we are prepared.

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An emergency response team composed of

central ofce personnel, teachers, and students

should be trained to respond to an emergency

in a science laboratory or classroom.

If an accident should occur, each member of

the team must be able to respond quickly and to

perform his or her role effectively to assist an

injured person and reduce damage to property.

The following list outlines some responsibilities that an emergency response team might perform.

This does not represent a complete list but should form the basis of emergency preparedness.

Practice regular re and evacuation drills.

Make sure that safety equipment is

accessible and operating correctly.

Inspect rst-aid kits and chemical spill

kits.

Monitor safety equipment regularly.

Compile and maintain a current le of

Material Safety Data Sheets (MSDS).

Practice responding to simulated

accidents and emergencies.

Identify which chemical spills to respond

to and which ones a professional HazMat

(Hazardous Materials) team should

handle.

Attend professional development on rst

aid, including CPR and abdominal thrust

procedures (Heimlich maneuver).

Document information about accidents,

and maintain these records for a

minimum of two years.

Emergency Response System

School personnel should organize an emergency response system at the beginning of the school year

before laboratory investigations and activities begin. This system should include clearly dened roles

and responsibilities for an Emergency Response Team (ERT). The ERT should be prepared to move

quickly and effectively when responding to accidents in order to reduce injury to a student or teacher,

and damage to property in a science classroom.

In addition, team members should take

preventative measures to ensure safety in the

laboratory by regularly checking equipment

and facilities.

Emergency Preparedness

Emergency Response Team

An example of how an emergency response team could respond to a re emergency follows

(Figure 4).

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EmErgEncy rEsponsE TEam

rEsponsEToa FirE EmErgEncy

Figure 4

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1. Failure to thoroughly plan and conduct a safe

activity

failure to incorporate safety into the

activity

use of unnecessary hazardous chemicals

following unsafe procedures and

methods

failure to plan for disposal of waste or

hazardous chemicals

lack of teaching experience and safety

training

failure to use and maintain discipline

failure to enforce safety rules

2. Failure of the teacher to give adequate, clear

instructions or perform thorough inspections

of equipment

incorrect instructions given to students,or students did not understand the

instructions before beginning the activity

failure to inspect equipment

failure to monitor students during the

activity

3. Unsafe activity design, chemicals, or

equipment

unsafe or improper planning of the

activity

improper or poorly designed equipment

failure to check to see if chemicals were

suitable or safe to use

4. Failure to provide safe laboratory work

areas

inadequate facilities: poor lighting and

ventilation

inadequate or inappropriate work space

only one exit in laboratory

improper storage area

inadequate maintenance and poor

housekeeping

5. Proper safety equipment not provided or

maintained

failure to provide re extinguishers

failure to maintain safety equipment

failure to provide safe equipment and

materials

lack of safety equipment: goggles, lab

aprons, fume hoods, showers,

eye/face wash stations

Causes o Laboratory AccidentsTo prevent accidents, it is necessary to identify the causes of accidents. The schools, teachers,

and students actions (or lack thereof) can contribute to many laboratory accidents. The following

information was adapted from Science Laboratory Safety and Chemical Waste Disposal for Texas

Science Teachers, Texas Education Agency,1990.

When the School or the Teacher Is at Fault

Teachers bring into the room much larger quantities of ammable materials for

demonstrations than they really need to do it, . . . said [James A. Kaufman, director

of the Laboratory Safety Institute, a Natick, Mass., nonprot that publishes classroom-

safety guidelines]. If an accident occurs, he pointed out, they have 100 times as much

[chemical] getting involved in whatever the problem is.

David J. Hoff

ScienceLab Safety Upgraded After Mishaps.

Education Week, 2003.

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12/1230 T S f S d d 2006

When the Student Is at Fault

1. Equipment or materials with unknown

defects

chemicals contaminated

chemical mislabeled

equipment with unknown defect

unknown tampering with equipment

before use

1. Failure to follow instructions and use safe

practices

safety rules not followed precautions and procedures not

followed

failure to understand what is to be done

lack of knowledge of the hazards

doing unauthorized experiments

working without approval

being disorderly

failure to have equipment approved by

the teacher

failure to follow teachers instructions

2. Failure to use personal protective equipment

failure to wear eye protection

improper clothing and shoes

failure to use fume hoods

improper use of protective equipment

3. Improper use of equipment or chemicals

failure to follow precautions

incorrect use of chemicals

use of wrong chemicals failure to follow instructions using an

instrument

failure to monitor experiment or

equipment in operation

4. Physical condition of the student

student was ill

student was fatiguednot attentive oralert

student was under the inuence of

alcohol or other drugs

student had poor manual dexterity or

skills

5. Mental attitude and knowledge

failure to understand the experiment

lack of knowledge needed to do the

experiment

lack of good judgment

too rushedresulted in clumsy work

habits

tried to use a shortcut that was

hazardous

inability to work cooperatively with

other students

tried procedures that were not safe

indulged in uncontrolled anger or

impulsive actions

failure to remain calm and in control

2. Other inuences

weatherelectrical surges or otherweather damage

failure of local power plants

vandalism of equipment

Other Factors

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